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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple style='word-wrap:break-word'><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt'>Redundancy also implies you keep the old working system as your fail over and deploy the new config and if that goes foobar you fail over back to the old known working system. So redundancy infact does cover these “f**k ups” too.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt'>Additionally, if there was a new config for the firewall, I would have expected that to be tested and validated in a test system (UAT) before being deployed live. These are common practices for much lesser systems. Don’t know what process they use, or the skill of their employees as far as robust enterprise systems go.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt'>73 de k1jbd<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt'>Bammi<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt'><o:p> </o:p></span></p><div><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal><b><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>From:</span></b><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> bars <bars-bounces@w1hh.org> <b>On Behalf Of </b>Tim K1DC<br><b>Sent:</b> Wednesday, June 19, 2024 11:47 PM<br><b>To:</b> bars@w1hh.org<br><b>Subject:</b> Re: [bars] 911 outage root cause revealed<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal style='margin-bottom:12.0pt'><span style='font-family:"Verdana",sans-serif'>Interesting... If one can take the report at face value they mention that the 911 centers could see the phone number of the caller and then was able to call them back. Assuming this is a VoIP system, honestly what phone system isn't these days, this tells me that the SIP traffic was making it through but the audio data was not. These are typically carried on different network ports and require specific firewall rules to allow them through. There is a common problem with VoIP system refereed to as 'one-way audio' in which the calls are connected but only one of the parties can hear the other. This situation is almost always caused by a misconfiguration of a firewall. It could also have been a defense mechanism whereby some firewalls can block specific ports if it sees 'unusual' activity on a port.<br><br>If this was the case no amount of redundancy/failover would have helped - the system wasn't down, calls were still going through.<br><br>73,<br><br>T.</span><o:p></o:p></p><div><p class=MsoNormal>On 06/19/2024 22:03, Juan Jiménez wrote:<o:p></o:p></p></div><blockquote style='margin-top:5.0pt;margin-bottom:5.0pt'><div><p class=MsoNormal><a href="https://www.boston25news.com/news/local/massachusetts-officials-reveal-cause-hourslong-911-system-outage/FA22RGI3QBB6FBPWLJMKO7SOFM/">https://www.boston25news.com/news/local/massachusetts-officials-reveal-cause-hourslong-911-system-outage/FA22RGI3QBB6FBPWLJMKO7SOFM/</a><o:p></o:p></p></div><p class=MsoNormal><br><br><o:p></o:p></p><pre>_______________________________________________<o:p></o:p></pre><pre>bars mailing list<o:p></o:p></pre><pre><a href="mailto:bars@w1hh.org">bars@w1hh.org</a><o:p></o:p></pre><pre><a href="http://mail.w1hh.org/mailman/listinfo/bars_w1hh.org">http://mail.w1hh.org/mailman/listinfo/bars_w1hh.org</a><o:p></o:p></pre></blockquote><p class=MsoNormal><o:p> </o:p></p></div></body></html>